How is this Possible?

That Crystal Affix All resist

U can get it… craft it from codex, with ur farming build (crystalized set), create 10-20 divination, go to 500++ floor and identifed all… if u have good luck, u can get that eternal divination with crystal affix… but sometimes u cant get it with max luck too… so brave ur self

if an Epic affix on the Crystal affix list is on a Legend or Eternal item, there is a chance when a Legend or Eternal item is found for that affix to be a Crystal affix. it the Legend or Eternal item has 2 or more affixes on it that are on the Crystal affix list, only one of them will become a Crystal affix. there can only be one Crystal affix on any one item. Set affix & Mythic affix are the same, only 1 of each on any 1 item. you could have one item with a Crystal, Set, & Mythic affix, and 3 other affixes.

here is a post on how hard it is to Craft Eternal Items. so this post and looking at an item in the Codex can help a lot to discover if someone cheated or not.